To complicate traffic analysis Sender can add a padding to his message before encrypting it for some remailer in chain. So that the message is shortened after decryption and stripping of pseudo headers. It can be done with a dummy header lines: ## Padding: fjx6zRURnnK1DV4CdL7gbHpnUiV1KbbRf5HatXiaD+ZPtH0 ... Also, for a length increment a remailer may understand commands like: ## Pad-length: 1K Pad-encrypt-for: remailer@replay.com It will then add the 'Padding:' header and re-encrypt the message with the appropriate remailer's public key. The next remailer in chain will see the padding and will try do decrypt the message twice... If stealth crypto is used, a random padding can be simply attached to the end of the message. Also, the remailer by itself can decide to increase a message length to cover some rare big messages. ---